This invention relates generally to turbine engines, and more particularly, to a method and apparatus that facilitates reducing stress in combustor support legs used in turbine engines.
At least some known combustors are supported at an aft end of the combustor by support legs. Known support legs control the axial, radial and circumferential location of the combustor in a core gas turbine engine, and generally include a plurality of openings, called windows. Cooling fluid is channeled through such windows towards downstream components, such as turbine components. Generally, known windows are rectangular-shaped, square-shaped or elliptical-shaped.
Known rectangular-shaped and square-shaped windows include rounded corners that are each formed with the same radius, and that are connected together with straight line segments extending between adjacent corners. Known elliptical windows include two straight line segments that are substantially parallel to each other, and that are also connected at respective ends by arcuate segments having the same radii. Furthermore, known support legs also include bolt holes that are used to couple the support legs to a combustor casing at alternating window locations.
The rounded corners and/or sides of known window configurations may develop high concentrations of stress during turbine operations. Over time the stresses induced to the windows may cause cracking adjacent to the corners and may lead to failure of the support leg and/or reduce the on-wing service time of the support legs. As a result and based on the high failure frequency and potential, known support legs are generally replaced more frequently, thereby increasing engine downtime and increasing maintenance costs.